"And a quick domain check would show that it isn't even registered to Microsoft!"

After some more cursory investigation it appears the vista live test is hosted on the same machine as exsilio's website. Still pretty sloppy for a MS project though but maybe it's not actually official yet and arch has beaten the official launch.
I can't help but also notice that exsilio's admins are some of those misguided souls that wrongly think that blocking ping and traceroute serves some kind of purpose.

Soulbender: I can't help but also notice that exsilio's admins are some of those misguided souls that wrongly think that blocking ping and traceroute serves some kind of purpose.

Have you never heard of the dreaded ping attack? That's when a ping with a red headband and a bare chest infiltrates your system, kills the scheduler and frees the POWs from the quarantine folder. Traceroute is even worse, it uses blue light!